Leading edge protection of a wind turbine blade

Abstract

The invention relates to a leading edge protection cover for a wind turbine blade. The protection cover comprises first and second longitudinally extending edges, and outer and inner arcuate surfaces extending there between. The inner arcuate surface is shaped to be attached to an outer surface portion of the wind turbine blade such as to cover at least a part of the leading edge of the blade, and with the first longitudinally extending edge being attached to a suction side of the wind turbine blade. The protection cover further comprises a number of vortex generating members positioned on the outer arcuate surface of the protection cover along at least a part of the first longitudinally extending edge. The proposed protection cover results in an increased protection of the wind turbine blade against impacting particles and improved fluid properties over the surface of the wind turbine blade. The invention further relates to a method of preparing a wind turbine blade with a leading edge protection cover, comprising the steps of moulding a leading edge protection cover comprising a number of vortex generating members and attaching the leading edge protection cover to an outer surface portion of the wind turbine blade.

1 . A leading edge protection cover for attachment to a wind turbine blade, the wind turbine blade extending longitudinally between a root end and a tip end of the blade, and extending transversely between a trailing edge and a leading edge, 
       wherein the protection cover comprises first and second longitudinally extending edges, and outer and inner arcuate surfaces extending there between, and the inner arcuate surface is shaped to be attached, in use, to an outer surface portion of the wind turbine blade comprising at least a part of the leading edge with the first longitudinally extending edge being attachable to a suction side of the wind turbine blade, and the protection cover is configured to be statically fixed to the wind turbine blade,
 wherein the protection cover further comprises a number of vortex generating members positioned on the outer arcuate surface of the protection cover along at least a part of the first longitudinally extending edge and the vortex generating members are formed integrally with the protection cover; and 
 the vortex generating members are positioned on the outer arcuate surface of the protection cover such that they project away from the outer surface portion of the wind turbine blade when the protection cover is attached to the blade. 
 
     
     
         2 . The leading edge protection cover according to  claim 1 , wherein the vortex generating members comprise a body of a tetrahedron-like shape protruding from the outer arcuate surface of the protection cover. 
     
     
         3 . The leading edge protection cover according to  claim 2 , wherein the tetrahedron-like shaped body comprises a pressure surface, a suction surface and a back surface, wherein the back surface faces towards the first longitudinally extending edge and the pressure surface faces towards the tip end or the root end of the blade when the protection cover is attached on the blade. 
     
     
         4 . The leading edge protection cover according to  claim 3 , wherein the pressure surface is curved inwardly. 
     
     
         5 . The leading edge protection cover according to  claim 3 , wherein the back surface extends substantially perpendicularly from the outer arcuate surface. 
     
     
         6 . The leading edge protection cover according to  claim 3 , wherein the pressure surface extends substantially perpendicularly from the outer arcuate surface. 
     
     
         7 . The leading edge protection cover according to  claim 1 , wherein the vortex generating members comprise a body of increasing height from the outer arcuate surface in a direction from the leading edge towards the first longitudinally extending edge. 
     
     
         8 . The leading edge protection cover according to  claim 1 , wherein the vortex generating members protrude a maximum height from the outer arcuate surface in the range of 0.2-0.7% of a chord length of the wind turbine blade and/or in the range of 2-10 mm. 
     
     
         9 . The leading edge protection cover according to  claim 1 , wherein the protective cover comprising the number of vortex generating members is moulded of a flexible plastic material such as a polyurethane or epoxy. 
     
     
         10 . The leading edge protection cover according to  claim 1 , wherein the vortex generating members are positioned with a distance between the vortex generating member and the first longitudinally extending edge, the distance being in the range of 2-30 mm such as in the range of 7-15 mm. 
     
     
         11 . A wind turbine blade extending a length between a root end and a tip end of the blade, and extending a width between a trailing edge and a leading edge, the wind turbine blade comprising an outer surface portion comprising at least a part of the leading edge,
 wherein the wind turbine further comprises a leading edge protection cover according to  claim 1  attached to the outer surface portion of the wind turbine blade and with the first longitudinally extending edge being attached to a suction side of the wind turbine blade.   
     
     
         12 . The wind turbine blade according to  claim 11 , wherein the protection cover is attached to the outer surface portion of the blade by an adhesive. 
     
     
         13 . The wind turbine blade according to  claim 11 , wherein the protection cover is attached to the outer surface portion of the blade by attachment means such as screws, bolts and/or rivets placed between the vortex generating means and the first longitudinally extending edge. 
     
     
         14 . The wind turbine blade according to  claim 13 , wherein the leading edge protection cover has a stiffness in the range of 500 MPa×mm to 250 GPa×mm, preferably the leading edge protection cover has a stiffness in the range of 1 GPa×mm to 100 GPa×mm. 
     
     
         15 . A method of preparing a wind turbine blade with a leading edge protection cover, the wind turbine blade extending a length between a root end and a tip end of the blade, and extending a width between a trailing edge and a leading edge, the wind turbine blade comprising an outer surface portion comprising at least a part of the leading edge, the method comprising:
 moulding a leading edge protection cover comprising a number of vortex generating members and according to  claim 1 ,   attaching the leading edge protection cover to the outer surface portion of the wind turbine blade such as to cover the part of the leading edge and such that the vortex generating members are positioned on a suction side of the wind turbine blade.   
     
     
         16 . The method of preparing a wind turbine blade according to  claim 15 , wherein the leading edge protection cover is moulded in a mould comprising a number of recesses for the moulding of the vortex generating members. 
     
     
         17 . The method of preparing a wind turbine blade according to  claim 15 , wherein the method steps form part of a manufacture of the wind turbine blade. 
     
     
         18 . The method of preparing a wind turbine blade according to  claim 15 , wherein the method step of attaching the leading edge protection cover is performed as post processing during repair or maintenance of the wind turbine blade.